#define HasChar()	(*((char *)0xfff0))
#define GetChar()	(*((char *)0xfff1))
#define PutChar(c)	(*((char *)0xfff2) = c)

char upper(char a) {
	int b = 1;
	return a - b;
}

void main() {
	char c;
	while (1) {
		if (HasChar()) {
			c = GetChar();
			c = upper(c);
			PutChar(c);
		}
	}
}
